The difference between computer users who get scammed and those who don’t often comes down to a simple checklist: In just-released research, AARP identifies 15 particular behaviors, life situations and knowledge attributes that significantly increase vulnerability to online fraud.

The kicker: Nearly 1 in 5 American adults – roughly 34 million people – engage in at least seven of them.

These eye-opening findings are pooled from detailed surveys of more than 11,000 adults across the U.S., comparing the online actions, behaviors and life experiences of fraud victims and non-victims – and providing a detailed “profile” of those who are most vulnerable to Internet-based scams.

In future blogs, we’ll delve deeper into how, where, when and why the dangers of online fraud lurk in the “Fraud-Likely 15.” (You can also keep tabs on other scams here and with free email alerts.) But for now, a snapshot of some key findings from this important AARP report,“Caught in the Scammer’s Net”:

Behaviors

In the past seven days before being surveyed, respondents admitted to:

Clicking on pop-up advertisements: Opened by 26 percent of victims compared to 10 percent of non-victims, pop-ups are often used to install computer malware or lead to surveys that glean personal information.

Selling products on online auction sites: 23 percent versus 7 percent. Scammers pose as buyers, paying with counterfeit checks or money orders – often for higher amounts than the sale price, with a request to send back the difference.

Purchasing a product through a money payment business: 47 percent versus 30 percent. When using these services, link them to a credit card, which offers more protection against fraud. There’s more risk linking to a checking or debit card account because if those systems are hacked, or someone gets your payment transfer information, your bank account is exposed to the scammer.

Signing up for “free trial” offers: 18 percent versus 8 percent engaged in these traps, which lock buyers into hard-to-cancel contracts – and merchandise may not arrive until after the trial ends.

Additionally, victims scored higher on several indicators of acting impulsively and admitted to posting more personal information online, such as birth dates, marital status, names of children and even Social Security numbers, that could be used for identity theft. They were also more likely to visit Web sites that required them to read privacy and terms of agreement statements – significant because those sites often require providing personal information.

Confirming previous research, the AARP report found that feeling vulnerable increases fraud vulnerability. So be extra careful when making decisions online (or in person). And take note, friends and family members, if loved ones are experiencing any of the following:

Feelings of isolation, reported by 2 in 3 victims, compared to a minority of non-victims

Loss of a job: 23 percent versus 10 percent

Negative change in financial status: 44 percent versus 23 percent

Being concerned about debt: 69 percent versus 57 percent

Other factors that increase vulnerability risk: stress about moving, personal or family illness, the death of a loved one, relationship issues and going through a divorce (which tripled the risk). Previous research shows that those 65 and older are most vulnerable to any type of scam within three years of such traumatic events.

Knowledge

When asked several questions about Internet safety, neither victims nor non-victims scored particularly well. But on two specific issues, victims were significantly less likely to answer correctly than non-victims:

Being unaware that banks do not send emails to customers asking them to click on a link to verify personal or account information. Nearly 2 in 3 victims, compared to 38 percent of non-victims, believe that banks do this, but it’s a common ruse by scammers to download malware or collect details for likely identity theft.

Being unaware that a Web site’s privacy policy does not mean the site will not share information from users. Roughly half of non-victims, compared to 40 percent of victims, were aware that information can be shared. However, such information may be sold either to legitimate vendors or to scammers posing as such, and used to compile to Sucker Lists to identify possible future victims.

For information about other scams, sign up for the Fraud Watch Network. You’ll receive free email alerts with tips and resources to help you spot and avoid identity theft and fraud. And you’ll gain access to a network of experts, law enforcement and people in your community who will keep you up to date on the latest scams in your area.